Aside from the twin beds (vs. a big queenish bed) in the cabover, this is not an atypical layout, if I'm understanding you properly. My '98 Coachmen Santara 315QB is pretty much exactly as described save for the cabover...and for the dinette and couch on opposite sides (i.e. the couch is on the driver's side and the dinette on the passenger side next to the entry door). The Cruise America 29ish foot models that they have for rent or ex-rental sale are also very similar in layout, as I recall.
Link to the floorplan; note that you could easily fit a couple of short people lengthwise in the cabover vs. sleeping widthwise.